Senior RF Systems Engineer

About the role

Castelion is bringing a new approach to defense development and production: short, iterative design cycles, rapid testing, and modern commercial manufacturing strategies for production at scale. We are designing, building, and testing next‑generation long‑range strike weapons systems to give America and its Allies a definitive edge and deter future conflicts. The Senior RF Systems Engineer will lead the design and development of a multi‑channel exciter/receiver subsystem that interfaces between RF hardware and digital baseband systems, owning the subsystem end‑to‑end from architecture and design through production.

Responsibilities

• Own the exciter/receiver subsystem end‑to‑end as both systems engineer and RF design lead, driving architecture, design, integration, and production readiness.
• Design and deliver a multi‑channel RF system bridging RF front‑end and digital baseband, optimizing for performance, cost, and manufacturability.
• Lead RF system modeling and analysis, including phase noise, spur analysis, gain, noise figure, compression, and dynamic range.
• Execute hands‑on design validation and debugging in the lab, using RF test equipment to ensure performance and reliability.
• Partner cross‑functionally with software, firmware, power, manufacturing, and test teams to ensure seamless system integration and scalable production.
• Collaborate with suppliers and fabrication partners to optimize RF PCB designs, improve technical performance, and reduce cost.
• Develop and influence test strategies and infrastructure that achieve lower cost and higher throughput than traditional approaches without sacrificing screening effectiveness.
• Drive design decisions that enable aggressive production goals and ensure resilience to supply chain disruptions.
• Deliver a solution that meets a target cost, significantly improving on traditional system costs.
• Establish a production‑first standard for the subsystem, improving design quality, reducing preventable errors, and minimizing the need for day‑to‑day oversight.
• Strengthen supplier relationships and technical engagement, enabling better responsiveness, more sourcing flexibility, and improved design‑for‑manufacturing outcomes.
• Consistently balance and deliver strong technical performance within real‑world constraints such as cost, schedule, and manufacturability.

Qualifications

• Bachelor's or Master's degree in Electrical Engineering, RF Engineering, or related field.
• Experience with high‑frequency RF PCB design.
• Proficiency in RF system modeling and analysis.
• Hands‑on experience with RF lab equipment and testing.
• Ability to design and analyze complex RF systems from architecture through implementation.

Preferred Skills

• Experience designing RF systems including phase noise budgeting, spur analysis, RF system synthesis, and performance modeling.
• Experience working with PCB fabrication houses to realize RF structures, understanding fabrication limits and cost drivers.
• Experience with RF simulation tools such as ADS, HFSS, or CST, including design verification and iteration.
• Familiarity with supplier capabilities and constraints across RF components and fabrication.
• Experience developing or supporting production test strategies.

Leadership Qualities

• Bias to action and creative problem solving.
• Willingness to question assumptions and bring breakthrough ideas from other industries.
• Ability to resolve minor development issues independently.
• High commitment and initiative.
• Strong sense of accountability, integrity, and clear communication.
• Proactive in communicating blockers and managing stakeholder relationships tactfully.
• Ability to thrive in a fast‑paced, autonomous, and demanding environment.

Benefits

• Long‑term stock incentives.
• Comprehensive medical, vision, and dental insurance.
• Three weeks of paid time off per year.

Eligibility (ITAR Requirements)

Applicants must be a U.S. citizen or national, a lawful permanent resident (green card holder), a refugee under 8 U.S.C. 1157, an asylee under 8 U.S.C. 1158, or be eligible to obtain the required authorizations from the U.S. Department of State.